package demo2;

import demo1.TestDemo;

class Cat {
    public int age;
}

class Dog extends Cat{
    public int age;
}
class A {

}
class B extends A{

}
class C extends B{

}
class D extends C {
//可以一直写下去
}

class Animals {
    public String color;
    public int age;
}

class wolf extends Animals{

}

class Tiger extends Animals{

}

public class Test extends TestDemo {
    public void test() {
        System.out.println(super.a);
    }

    public static void main(String[] args) {
        Test t = new Test();
        t.test();
    }
}
